Use the Fragmentation view in the Database Manager window to display fragmentation
reactions in all your libraries and to create and manage fragmentation mechanism databases in your editable libraries.
The Fragmentation view contains a graphical editor for entering fragmentation reactions,
which you can store in the library database with complementary information for the reaction. You can search all fields of the database, such as authors, ionization method, mass analyzer, or structures.
The fragmentation library uses an expert system to automatically extract a decomposition
mechanism for each fragmentation reaction in the database and determine the compound class range to which you can apply the mechanism. This system applies database mechanisms to your structures and automatically predicts the fragmentation reactions for a specified compound.
HighChem collated and entered fragmentation mechanisms published in all the available
printed media dedicated to mass spectrometry. Each reaction, along with related chemical structures, was manually drawn in Reaction Editor and saved in the HighChem Fragmentation Library, which currently contains approximately 130
000 individual reactions. See Fragmentation mechanisms from the library
. Fragmentation pathways are accompanied with complementary information such as the title, the authors, and the information source. This library collection serves as a knowledge base for predicting fragmentation pathways from your structures.
To ensure the data is of the highest quality, the software rigorously evaluates fragmentation
mechanisms in two stages: manual and automatic. The manual evaluation includes accuracy and plausibility assessments of reaction mechanisms and consistency checking between fragment masses and peak m/z
values if the spectrum is available. The automatic evaluation includes simple element, charge, and radical consistency checks on both sides of the reaction and newly developed algorithms for complex electron mapping that has revealed formally erroneous mechanisms. Both stages have uncovered numerous problems and errors regarding mechanisms, and HighChem has either made the appropriate corrections or excluded these mechanisms from the library.